<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/welcome' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>

    <!-- 卡片布局 -->
    <el-card>
      <!-- el-alert提示框 -->
      <el-alert
        title="注意：只允许为第三级分类设置相关参数"
        type="warning"
        show-icon
        :closable="false"
      >
      </el-alert>
      <!-- 选择商品分类区域:这里用了Layout布局 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
            class="back"
            clearable
            v-model="selectedCateKeys"
            :options="cateList"
            :props="cateProps"
            @change="handleChanged"
          ></el-cascader>
        </el-col>
      </el-row>
      <!-- Tab页签区 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数的按钮 -->
          <el-button
            type="primary"
            size="mini"
            :disabled="isBtnDisabled"
            @click="addDialogVisible = true"
            >添加参数</el-button
          >
          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag
                  v-for="(item, i) in scope.row.attr_vals"
                  :key="i"
                  closable
                  @close="handleClose(i, scope.row)"
                >
                  {{ item }}
                </el-tag>
                <!-- 输入文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加的按钮 -->
                <el-button
                  v-else
                  class="button-new-tag"
                  size="small"
                  @click="showInput(scope.row)"
                  >+ New Tag</el-button
                >
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index" label="序号"> </el-table-column>
            <el-table-column label="参数名称" prop="attr_name">
            </el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button
                  size="mini"
                  type="primary"
                  icon="el-icon-edit"
                  @click="showEditDialog(scope.row.attr_id)"
                  >编辑</el-button
                >
                <el-button
                  size="mini"
                  type="danger"
                  icon="el-icon-delete"
                  @click="removeParams(scope.row.attr_id)"
                  >删除</el-button
                >
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加属性的按钮 -->
          <el-button
            type="primary"
            size="mini"
            :disabled="isBtnDisabled"
            @click="addDialogVisible = true"
            >添加属性</el-button
          >
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <el-tag
                  v-for="(item, i) in scope.row.attr_vals"
                  :key="i"
                  closable
                  @close="handleClose(i, scope.row)"
                >
                  {{ item }}
                </el-tag>
                <!-- 输入文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加的按钮 -->
                <el-button
                  v-else
                  class="button-new-tag"
                  size="small"
                  @click="showInput(scope.row)"
                  >+ New Tag</el-button
                >
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index" label="序号"> </el-table-column>
            <el-table-column label="参数名称" prop="attr_name">
            </el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button
                  size="mini"
                  type="primary"
                  icon="el-icon-edit"
                  @click="showEditDialog(scope.row.attr_id)"
                  >编辑</el-button
                >
                <el-button
                  size="mini"
                  type="danger"
                  icon="el-icon-delete"
                  @click="removeParams(scope.row.attr_id)"
                  >删除</el-button
                >
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- “添加参数和属性的”对话框 -->
    <el-dialog
      :title="titleText"
      :visible.sync="addDialogVisible"
      width="50%"
      @close="addDialogClosed"
    >
      <!-- 内容主体区：表单 -->
      <el-form
        :model="addForm"
        :rules="addFormrules"
        ref="addFormRef"
        label-width="100px"
      >
        <el-form-item label="写入数据" prop="attr_name">
          <el-input
            v-model="addForm.attr_name"
            placeholder="请输入一定长度的数据"
          ></el-input>
        </el-form-item>
      </el-form>
      <!-- 底部区域 -->
      <template #footer>
        <span class="dialog-footer">
          <el-button @click="addDialogVisible = false">取 消</el-button>
          <el-button type="primary" @click="addParams">确 定</el-button>
        </span>
      </template>
    </el-dialog>
    <!-- “修改属性参数”的对话框 -->
    <el-dialog
      title="修改"
      :visible.sync="editDialogVisible"
      width="50%"
      @close="editDialogClosed"
    >
      <!-- 内容主体区：表单 -->
      <el-form
        :model="editForm"
        :rules="editFormrules"
        ref="editFormRef"
        label-width="100px"
      >
        <el-form-item label="写入数据" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <!-- 底部区域 -->
      <template #footer>
        <span class="dialog-footer">
          <el-button @click="editDialogVisible = false">取 消</el-button>
          <el-button type="primary" @click="editParams">确 定</el-button>
        </span>
      </template>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data() {
    return {
      // 商品分类列表
      cateList: [],
      // 级联选项框的配置对象
      cateProps: {
        expandTrigger: 'hover',
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      // 级联选择框双向绑定到的数组
      selectedCateKeys: [],
      // 被激活的页签的名称
      activeName: 'many',
      // Tab页签的数据
      manyTableData: [],
      onlyTableData: [],
      // 控制对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据对象
      addForm: { attr_name: '' },
      // 添加参数的验证规则对象
      addFormrules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      },
      // 控制修改对话框的显示与隐藏
      editDialogVisible: false,
      // 修改的表单数据对象
      editForm: {},
      // 修改的表单的验证规则
      editFormrules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      }
    }
  },
  created() {
    // 获取所有的商品分类列表
    this.getCateList()
  },
  methods: {
    // 获取商品分类
    async getCateList() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品分类失败')
      }
      this.cateList = res.data
    },
    // 级联选择框变化，会触发该函数
    async handleChanged() {
      this.getParamsData()
    },
    // Tab页签点击事件的处理函数
    handleTabClick() {
      // console.log(this.activeName)
      this.getParamsData()
    },
    // 获取参数的列表数据
    async getParamsData() {
      // 如果选中的不是三级分类，就清空
      if (this.selectedCateKeys.length !== 3) {
        this.selectedCateKeys = []
        // 表格内容也清空
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      // 如果是三级分类，就显示呗
      console.log(this.selectedCateKeys)
      // 根据所选分类的Id，和当前所处的面板，获取对应的参数
      const { data: res } = await this.$http.get(
        `categories/${this.cateId}/attributes`,
        {
          params: { sel: this.activeName }
        }
      )
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品分类失败')
      }

      // 将获取到的数据的每一项的attr_vals写为数组形式，再渲染到展开行中
      res.data.forEach(item => {
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制文本框的显示与隐藏
        item.inputVisible = false
        // 双向绑定文本框的值
        item.inputValue = ''
      })
      console.log(res.data)
      // 判断一下获取到的属性究竟是哪个页签的，渲染对应的页面
      if (this.activeName === 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }
    },
    // 监听对话框的关闭事件
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },
    // 监听对话框的确定键
    addParams() {
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.post(
          `categories/${this.cateId}/attributes`,
          {
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          }
        )
        console.log('我到这了')
        if (res.meta.status !== 201) {
          return this.$message.error('添加参数失败')
        }
        this.$message.success('添加参数成功！')
        this.addDialogVisible = false
        this.getParamsData()
      })
    },
    // 点击按钮，展示修改对话框。这里之所以写成函数，是因为不仅要显示对话框，还要读取对话框中的数据
    async showEditDialog(attrid) {
      const { data: res } = await this.$http.get(
        `categories/${this.cateId}/attributes/${attrid}`,
        {
          params: { attr_sel: this.activeName }
        }
      )
      if (res.meta.status !== 200) {
        return this.$message.error('获取参数信息失败')
      }
      this.editForm = res.data
      this.editDialogVisible = true
    },
    // 重置修改的表单
    editDialogClosed() {
      this.$refs.editFormRef.resetFields()
    },
    // 点击确定以后的操作
    editParams() {
      this.$refs.editFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.put(
          `categories/${this.cateId}/attributes/${this.editForm.attr_id}`,
          {
            attr_name: this.editForm.attr_name,
            attr_sel: this.activeName
          }
        )

        if (res.meta.status !== 200) {
          return this.$message.error('修改参数失败')
        }
        this.$message.success('修改参数成功！')
        this.editDialogVisible = false
        this.getParamsData()
      })
    },
    // 根据id删除对应的数据项
    async removeParams(attrid) {
      // 弹框操作
      const confirmResult = await this.$confirm(
        '此操作将永久删除该属性, 是否继续?',
        '提示',
        {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }
      ).catch(err => err)
      if (confirmResult !== 'confirm') {
        return this.$message.info('已经取消删除了')
      }
      // 删除的业务逻辑
      const { data: res } = await this.$http.delete(
        `categories/${this.cateId}/attributes/${attrid}`
      )
      if (res.meta.status !== 200) {
        return this.$message.error('删除用户失败')
      }
      this.$message.success('删除用户成功')
      this.getParamsData()
    },
    // 添加、删除Tag按钮与后台进行交互
    async saveAttrVals(row) {
      // 这里是将输入文本添加到后端数据库
      const { data: res } = await this.$http.put(
        `categories/${this.cateId}/attributes/${row.attr_id}`,
        {
          attr_name: row.attr_name,
          attr_sel: row.attr_sel,
          attr_vals: row.attr_vals.join(' ')
        }
      )
      if (res.meta.status !== 200) {
        return this.$message.error('修改参数失败')
      }
      return this.$message.success('修改成功')
    },
    // 文本框失去焦点或按下Enter都会触发的函数
    async handleInputConfirm(row) {
      // 在将文本框隐藏之前，还应清空其中不合法的内容
      if (row.inputValue.trim().length === 0) {
        row.inputValue = ''
        row.inputVisible = false
        return this.$message.error('你输入的内容不合法')
      }
      // 如果没有return，即如果输入内容合法，就进一步处理，将获得的值添加到el-tag的数组中再渲染就好了
      // 这里是将输入文本添加到前端
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      // 这里将输入改到后端
      this.saveAttrVals(row)
    },

    // 点击Tag添加按钮，展示文本输入框
    showInput(row) {
      row.inputVisible = true
      // 让文本框自动获得焦点
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    // 删除对应的参数可选项
    handleClose(i, row) {
      row.attr_vals.splice(i, 1)
      this.saveAttrVals(row)
    }
  },
  computed: {
    // 如果按钮需要被禁用，则返回true。否则返回false
    // 而该按钮的禁用与否都和selectedCateKeys数组有关
    isBtnDisabled() {
      if (this.selectedCateKeys.length !== 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类的Id,这个计算属性可用于后台访问
    cateId() {
      if (this.selectedCateKeys.length === 3) {
        return this.selectedCateKeys[2]
      }
      return null
    },
    // 动态计算标题的文本
    titleText() {
      if (this.activeName === 'many') {
        return '添加动态参数'
      } else {
        return '添加静态属性'
      }
    }
  }
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 15px 0;
}
.el-tag {
  margin: 10px;
}
.input-new-tag {
  width: 120px;
}
</style>
